Which weighs more, air or propane vapor?

Propane vapor is denser than air, which is why it is the correct answer. Propane has a molecular weight of about 44 g/mol, while the average molecular weight of air, primarily composed of nitrogen and oxygen, is approximately 29 g/mol. This means that propane vapor, when released, is heavier than air and tends to settle at lower levels, especially in confined spaces.

Understanding this characteristic is important for safety measures in cases where propane is used or stored, as it can lead to the accumulation of flammable vapor in low-lying areas if ventilation is inadequate. Recognizing the weight differences helps in assessing potential hazards and ensuring proper safety protocols are in place.